A1 Segment Research Articles

Abstract TP10: Realtime Tenecteplase Recanalization Rates And Clinical Outcomes In Patients With Medium Vessel Occlusion Stroke

Introduction: The goal of this study was to evaluate recanalization rates, incidence of hemorrhagic transformation, and clinical outcomes in patients with medium vessel occlusion (MVO) strokes receiving tenecteplase (TNK) and endovascular treatment (EVT) to add to the growing fund of knowledge of TNK in AIS. Methods: We conducted a retrospective cohort study of prospectively collected AIS patients who received TNK and EVT from October 2020 to June 2022 at our comprehensive stroke center. We included subjects with MVO defined as occlusion of the M2 segment or more distal of the middle cerebral artery without involvement of the M1 segment, A1 segment or more distal of the anterior cerebral artery, or P1 segment or more distal of the posterior cerebral artery. Patients receiving intra-arterial thrombolytics or non-thrombolytics were excluded. We defined successful recanalization as Modified Thrombolysis in Cerebral Infarction (mTICI) 2b or greater and symptomatic hemorrhage as change in NIHSS ≥ 4 with temporally associated hemorrhage. Hemorrhagic transformation was classified using ECASS-3 criteria. Social science statistics software was used for data analysis. Results: Out of 77 patients who received TNK and EVT, 16 subjects had MVO and were included in analysis. Mean age was 68.56 (95% CI 60.20, 76.93). Fifty six percent (n=9) of subjects were female. Median presenting NIHSS was 10.5 (95% CI 7.17, 14.07). Median 90 day mRS was 1 (95% CI 0.76, 2.62). No subject recanalized prior to EVT. Hemorrhagic transformation occurred in 43.75% (n=7) of subjects, and symptomatic intracerebral hemorrhage (ICH) occurred in 1 subject (6.25%) with PH-2. There was no ICH in subjects who did not recanalize post-EVT (n=3). No significant change was found from baseline NIHSS compared to discharge NIHSS (U=95.5, z=1.21, p=0.11). Conclusions: TNK in MVO may be associated with increased risk of hemorrhagic transformation. However, given that all subjects underwent EVT and the known incidence of post-procedural contrast staining on CT, the incidence of asymptomatic hemorrhagic transformation may be overestimated. This is further supported by good clinical outcomes and low incidence of symptomatic ICH.

Abstract TMP86: Clinical Outcomes Of Endovascular Thrombectomy Versus Acute Medical Treatment In Acute Ischemic Strokes Secondary To Medium Vessel Occlusion

Introduction: Acute ischemic stroke (AIS) from arterial occlusions are treated with emergent endovascular thrombectomy (EVT) when clinically appropriate. Clinical outcomes of EVT in medium vessel occlusion (MVO) compared to large vessel occlusion (LVO) have neither been well established nor compared to alternate medical management. Our aim was to evaluate outcomes of patients with AIS secondary to MVO undergoing EVT. Methods: We conducted a retrospective chart review of patients presenting to with MVO-associated AIS undergoing EVT or aggressive intra-arterial thrombolytic treatment with concurrent administration of IV eptifibatide. We assessed occlusion site, NIHSS (presentation, 7 day or discharge, 3 months), mRS (baseline, 90-day), and intracranial hemorrhage (ICH) rate. MVO was defined as occlusion of pure M2 middle cerebral artery without M1 segment involvement, anterior cerebral artery A1 segment or more distal, and posterior cerebral artery P1 segment or more distal. Mann-Whitney U test, Fisher exact test statistic, and T-test statistic were used for analysis. Results: From August 2020 to December 2021, out of 175 patients who underwent EVT, 50 had MVO (n=33 M2 occlusion, n=12 M3 occlusion, n=1 for P1, P2, A1, A2, A3 each). Twelve subjects with MVO received aggressive medical management with concurrent IV eptifibatide. Subjects between arms were similar at baseline (median NIHSS 11 [95% CI 10.75, 14.32]; mean age 71.5 [95% CI 69.24, 73.77]; male 48.39% [n=30]). The difference between initial NIHSS and discharge NIHSS was statistically significant in the EVT arm (Z-Score=4.03; p-value < .00001) but not in the medical arm (Z-score=1.96; p-value 0.05). Hemorrhagic transformation occurred in 28% (n=14) of EVT arm and 16.67% (n=2) of medical arm. This was not statistically significant (Fisher value: 0.71). Median 90 day mRS was 1 (95% CI [0.89, 2.11]). The difference between 90 day mRS was not significantly different (Z-score=-1.20; p-value 0.23). Conclusion: In our patient cohort, endovascular therapy was safe in medium vessel occlusion and may have more favorable clinical outcomes as illustrated by higher delta NIHSS in the endovascular thrombectomy group. Larger, prospective studies are needed to validate our results.

Mini anterior interhemispheric approach for A3 segment distal anterior cerebral artery aneurysms

IntroductionAneurysms of the A3 segment of the distal anterior cerebral artery (DACA), in relation to the genu of the corpus callosum, are specific sub-group which pose unique surgical challenges due to their discrete anatomical location. We describe a mini-anterior interhemispheric approach which can be safely utilised to clip these aneurysms rather than the traditional bifrontal approach. MethodsRetrospective analysis of the clinical and radiological data of ruptured DACA-A3 aneurysms operated between 2014 and 2021 at our institute. A curvilinear scalp incision within the hairline followed by raising small, unilateral, free frontal bone flap, avoiding the opening of frontal sinus. Superior sagittal sinus is displaced medially, inter-hemispheric dissection carried out with posterior trajectory and small callosotomy is performed. DACA is skeletonised, proximal control is established, and the A3 aneurysm is dissected and clipped. ResultOur cohort of 18 patients had a definite female preponderance (F:M::2:1) with mean age of 55.6 years. On admission three patients were categorized as WFNS Grade I, thirteen in Grade II, and two in Grade III for subarachnoid haemorrhage. All the patients had evidence of blood in the interhemispheric fissure; intraparenchymal haemorrhage was seen in seven, with intraventricular haemorrhage in six patients. Within the A3 segment six aneurysms were infragenu (inferior), eight were at the genu (anterior) and four were supragenu (superior). Two (11.1%) elderly patients succumbed post-surgery following ischemic infarcts and associated complications. At the time of follow-up at 3 months of the remaining sixteen (72.2%) patients, thirteen had a good outcome (mRS 0–3) and three (16.7%) had a poor outcome (mRS > 3). ConclusionThe mini anterior interhemispheric is an effective minimally invasive alternative for A3 segments aneurysms and helps to avoid the complications of the conventional bifrontal interhemispheric approach.

PS-R06-5: CASE REPORT OF INCREASED ARTERIAL STIFFNESS IN MOYAMOYA DISEASE IN A YOUNG CHINESE PATIENT PRESENTING AS RECURRENT STROKE IN SINGAPORE

Introduction: Moyamoya disease (MMD) is characterised by progressive stenosis of distal ICA and the resulting hazy network of basal collateral vessels. Increase arterial stiffness in MMD is not well described. Case report: We describe a young patient ML, a 42-year-old Chinese female, presented to hospital in June 2015 with headaches, on a background of known hypertension diagnosed at the age of 28 years. Her systemic examination was normal. Investigations were unremarkable. She was followed in General Medicine (GM) clinic from 2015, which ruled out secondary causes of hypertension, including renovascular disease, renal artery stenosis, phaeochromocytoma and hyperthyroidism. ML was treated for presumptive essential hypertension. Over time, her BP remained stable on candesartan 16 mg and bisoprolol 2.5 mg once daily. She continued to have intermittent headaches. Recurrent ischaemic strokes and diagnosis of Moyamoya disease ML presented with intermittent right-sided facial numbness in February 2017. A magnetic resonance imaging (MRI) brain done showed no acute infarct or hemorrhage, but moderately severe narrowing of the left terminal internal carotid artery (ICA), associated with poor flow signals in both the A1 segment of the left anterior cerebral artery (ACA) and the M1 segment of the left middle cerebral artery (MCA). She was started on clopidogrel 75 mg and atorvastatin 40 mg daily. The second stroke occurred in March 2019, when ML presented with acute right upper and lower limb weakness, and right facial, upper and lower limb numbness. Magnetic resonance angiography (MRA) demonstrated severe stenosis at the left terminal ICA, also involving the left M1 and A1 segments; collateral flow was observed. The third stroke happened in April 2019, presenting with acute right-sided facial and upper limb weakness, with BP of 201/86mmHg. MRI and MRA of the brain revealed new acute infarcts scattered in the territories of the left MCA and ACA. A CT angiogram re-demonstrated severe steno-occlusive disease involving the left ICA T-junction and left M1 and A1 segments, with extensive basal collaterals. In light of these findings, Moyamoya disease (MMD) was diagnosed. ML underwent a left external carotid-internal carotid bypass in June 2019. An arterial stiffness study by syphgmoCor in June 2020 using markedly increased arterial stiffness. Conclusion: We present first and very rare case of hypertension in a young patient with MMD associated with increased arterial stiffness. Systemic vascular affection in MMD may be the cause of increased arterial stiffness.

A Histomorphometric Analysis of Interganglionic Distance in the Myenteric Plexus of the Entire Large Intestine of Aborted Human Foetuses: A Cross-sectional Study

Introduction: The Enteric Nervous System (ENS) contributes to the innervation of the gut and is considered the second brain in the gut. It is a part of the peripheral nervous system and the ganglionated plexus (GP) of enteric neurons, present in the layers of the digestive tract, is more complex than any other structure of the peripheral nervous system. The establishment of a valid standard method for quantitative analysis of the myenteric plexus has been a topic of debate among enteric neuropathologists and is essential for better characterisation of patients with gut dysmotility. Aim: To determine the histomorphometric analysis of the interganglion distance of the myenteric plexus in the entire large intestine of aborted human foetuses. Materials and Methods: A cross-sectional descriptive study was carried out in the Department of Anatomy at Pondicherry Institute of Medical Sciences, Pondicherry, India. The study duration was eight years and seven months, from October 2014 to May 2022. A total of 50 aborted human foetus samples were collected from Rajiv Gandhi Government Women and Children’s Hospital, Puducherry, India, from the Department of Obstetrics and Gynaecology. The age of the aborted human foetuses was determined based on Biparietal Diameter (BPD) and Crown Rump Length (CRL) and correlated with clinical history. The aborted human foetuses were assigned to two groups: group A (n=29), ≤20 Weeks of Gestation (WG), and group B (n=21), ≥20 WG. Nicotinamide Adenine Dinucleotide Phosphate (NADPH) diaphorase histochemistry, an enzyme histochemistry technique, was used to study the tissue preparations. Statistical significance was determined using Statistical Package for Social Sciences (SPSS) version 20.0, International Business Machines (IBM) corporation. The independent sample t-test was conducted for parametric analysis. Results: The interganglion distance was measured from the caecum (A1 segment) to the anal canal (A7 segment) in aborted foetuses of less than 20 WG. The mean values ranged from 78.86±38.09 μm to 126.94±23.87 μm in foetuses of less than 20 WG. The mean values ranged from 66.41±8.05 μm to 107.67±30.17 μm in aborted human foetuses of more than 20 WG. Conclusion: The anal canal showed a long interganglion distance. The average reference values were found to be helpful as a diagnostic tool for identifying disorders related to gut innervation and motility.

Endovascular Treatment for Ruptured Proximal Anterior Cerebral Artery Dissecting Aneurysm: A Case Series.

Subarachnoid hemorrhage due to the A1 segment of an anterior cerebral artery dissecting aneurysm is rare. Therefore, a standard treatment has not been established. Though several case reports of direct surgery exist, there are few reports on endovascular treatment. This is the first study to describe five patients who underwent endovascular treatment for ruptured A1 dissecting aneurysms. Between January 2001 and December 2022 in our affiliated centers, five cases of SAH-onset A1 dissecting aneurysms were treated with endovascular treatment. We describe in detail two representative cases, briefly summarize the other three, and analyze their complications and outcomes. In the five cases, four were female. Four were in their 50s, and one was in her 80s. The WFNS grades were as follows: three were 2, one was 4, and one was 5. No re-ruptures or symptomatic complications were observed. The modified Rankin Scale scores at the time of discharge were as follows; one was 0, one was 1, two were 2, and one was 5. One in five patients needed retreatment after endovascular trapping because of recanalization. Endovascular treatment may be an effective and viable treatment option for ruptured A1 dissecting aneurysms. Further studies are needed to collect detailed data on complications and outcomes.

Abstract 15523: Breaking Bad - Severe Mechanical Hemolytic Anemia After Failed Mitral Valve Repair

Introduction: Hemolytic anemia is a rare complication of mitral valve repair surgery. Mechanisms include a high-velocity regurgitant jet striking the annuloplasty ring or displacement of the annuloplasty ring with para-annular leak. Case Report: A 66 year old man with a past history of coronary artery disease was found to have severe, eccentric mitral regurgitation (MR) due to anterior mitral valve leaflet prolapse/flail at the A2 segment. At another institution, he underwent surgical mitral valve repair involving chordal transfer from P2 to A2 segment, suture closure of the resulting P2 defect, and ring annuloplasty. Intra-operative transesophageal echocardiography confirmed the elimination of MR. Three weeks later the patient presented with fatigue and cola-colored urine. Physical examination revealed a murmur of MR. Lab tests were consistent with severe hemolytic anemia, including hemoglobin of 6 g/dL, indirect hyperbilirubinemia, elevated lactate dehydrogenase, and a low haptoglobin level. Peripheral blood smear showed dysmorphic red blood cells suggestive of mechanical lysis. The patient required multiple transfusions of packed red blood cells. Acute kidney injury developed and was attributed to pigment nephropathy. He was transferred to our institution. Decision-making: Recurrent MR from failure of recent mitral valve repair was suspected. Transthoracic and transesophageal echocardiography confirmed severe eccentric MR. The Heart Team recommended re-operation. In the operating room, the suture repair of the P2 defect was found to have dehisced. Re-repair was deemed infeasible, and the mitral valve was replaced with a porcine bioprosthesis. Post-operatively, hemolysis resolved and renal function recovered. Conclusion: This case illustrates the importance of suspecting hemolysis from recurrent MR in patients presenting with unexplained anemia after mitral valve surgery. Re-operation is generally required to treat this rare condition.

Opposite L-configuration double stenting for rupture of an extremely wide-necked anterior communicating artery aneurysm at the acute stage: illustrative case.

Wide-necked aneurysms can be treated by double stenting in an X- or Y-configuration or by a double waffle-cone technique. However, some aneurysms remain untreatable. The rupture of a complex wide-necked anterior communicating artery (AcomA) aneurysm that caused acute subarachnoid hemorrhage (SAH) was treated successfully using double stents with an opposite L-configuration as an alternative to the X-stent technique. The aneurysm involved both A1-A2 junctions in the aneurysm neck with acutely oriented A2 segments of the anterior cerebral artery bilaterally. It was densely packed and completely obliterated angiographically with preserved blood flow by implanting each stent in the ipsilateral A1-A2 bilaterally. Blood flow from the left A1 to the right A2 was confirmed through the AcomA on injection of the left internal carotid artery immediately after the procedure without critical infarction in the subthalamic area. Although the AcomA was not demonstrated by injection of the left internal carotid artery on angiography at 3 months or 1 year later, no cerebral infarction was seen on magnetic resonance images at the final hospital visit. Opposite L-configuration double stenting was used successfully as rescue stent-assisted coiling for a rupture of a complex wide-necked AcomA aneurysm in a patient with acute SAH.

Improved Blood Suppression of Motion-Sensitized Driven Equilibrium in High-Resolution Whole-Brain Vessel Wall Imaging: Comparison of Contrast-Enhanced 3D T1-Weighted FSE with Motion-Sensitized Driven Equilibrium and Delay Alternating with Nutation for Tailored Excitation.

High-resolution vessel wall MR imaging is prone to slow-flow artifacts, particularly when gadolinium shortens the T1 relaxation time of blood. This study aimed to determine the optimal preparation pulses for contrast-enhanced high-resolution vessel wall MR imaging. Fifty patients who underwent both motion-sensitized driven equilibrium and delay alternating with nutation for tailored excitation (DANTE) preparation pulses with contrast-enhanced 3D-T1-FSE were retrospectively included. Qualitative analysis was performed using a 4-grade visual scoring system for black-blood performance in the small-sized intracranial vessels, overall image quality, severity of artifacts, and the degree of blood suppression in all cortical veins as well as transverse sinuses. Quantitative analysis of the M1 segment of the MCA was also performed. The qualitative analysis revealed that motion-sensitized driven equilibrium demonstrated a significantly higher black-blood score than DANTE in contrast-enhanced 3D-T1-FSE of the A3 segment (3.90 versus 3.58, P < .001); M3 (3.72 versus 3.26, P = .004); P2 to P3 (3.86 versus 3.64, P = .017); the internal cerebral vein (3.72 versus 2.32, P < .001); and overall cortical veins (3.30 versus 2.74, P < .001); and transverse sinuses (2.82 versus 2.38, P < .001). SNRlumen, contrast-to noise ratiowall-lumen, and SNRwall in the M1 vessel were not significantly different between the 2 preparation pulses (all, P > .05). Motion-sensitized driven equilibrium demonstrated improved blood suppression on contrast-enhanced 3D-T1-FSE in the small intracranial arteries and veins compared with DANTE. Motion-sensitized driven equilibrium is a useful preparation pulse for high-resolution vessel wall MR imaging to decrease venous contamination and suppress slow-flow artifacts when using contrast enhancement.

Reference Values of Cerebral Artery Diameters of the Anterior Circulation by Digital Subtraction Angiography: A Retrospective Study.

A threshold-based classification of cerebral vasospasm needs reference values for intracranial vessel diameters on digital subtraction angiography (DSA). We aimed to generate adjusted reference values for this purpose by retrospectively analyzing angiograms and potential influencing factors on vessel diameters. Angiograms of the anterior circulation were evaluated in 278 patients aged 18–81 years. The vessel diameters of 453 angiograms (175 bilateral) were gathered from nine defined measuring sites. The effect sizes of physical characteristics (i.e., body weight and height, body mass index, gender, age, and cranial side) and anatomical variations were calculated with MANOVA. Segments bearing aneurysms were excluded for the calculation of reference values. Adjusted vessel diameters were calculated via linear regression analysis of the vessel diameter data. Vessel diameters increased with age and body height. Male and right-sided vessels were larger in diameter. Of the anatomical variations, only the hypoplastic/aplastic A1 segment had a significant influence (p < 0.05) on values of the anterior cerebral artery and the internal carotid artery with a small effect size (|ω2| > 0.01) being excluded from the reference values. We provide gender-, age-, and side-adjusted reference values and nomograms of arterial vessel diameters in the anterior circulation.

ASSOCIATION OF NF-1 AND MOYAMOYA SYNDROME : CASE REPORT

Neurofibromatosis type 1 (NF-1) is the most prevalent autosomal dominant genetic disorder. NF-1 vasculopathy is a significant complication of the disease. It affects both arterial and venous blood vessels of all sizes. Also Moyamoya syndrome is a cerebral vasculopathy . It is rarely detected with NF-1 in the pediatric group. Herein, we report of a 5 year-old male with NF1 and moyamoya syndrome. A 6-month-old baby boy was brought by his family with the complaint of brown spots on the body. On physical examination, cafe au lait spots on the body, subcutaneous nodule in the occipital area and hypotonicity were found. He was examined considering neurofibromatosis, one of the neurocutaneous diseases. Abdominal ultrasonography, brain MRI, echocardiyography, electroencephalography were normal. There was no pathological evidence in eye examination. In genetic tests, NF1 p.GIn2217 gene was found heterozygous positive. patient was followed up with annual brain MRI. Hamartomatous lesions in left putamen and left thalamus posterior were detected in brain MRI when the patient was two years old. There was no pathological evidence on norological physical excamination. When he was three years old thickening and enhancement of the right optic nerve was found in MRI due to possible optic glioma. Only in the left cerebellar hemisphere, two millimeter-sized hamartomatous lesions in the white matter were found to have newly developed. Both internal carotid arteries (ICA) are thinned from the supraclinoid segment. Middle cerebral artery (MCA) M1 segment on the right and anterior cerebral artery (ACA) A1 segment on the left could not be selected. Many thin collateral vascular structures were selected in these localizations and were found to be significant in terms of Moyamoya disease.Regression was detected in right optic glioma. No predisposing factor was found in the examinations of the patient for thrombosis. Acetyl salicylic acid prophylaxis was started. The patient was taken under neurosurgery follow-up for revascularization surgery. The follow-up and treatment continues. Association of NF-1 and Moyamoya syndrome is rare, but carries a potential risk of clinicoradiological progression. Closed monitoring of children with neurofibromatosis type 1 enables early diagnosis of moyamoya syndrome. Revascularization surgery may effective way to prevent progression of clinical symptoms, but long-term results require close follow-up studies.

Transcallosal and Pericallosal Courses of the Anterior Cerebral Artery.

(1) Background: The anterior cerebral artery (ACA) has a precommunicating A1 segment, followed by a postcommunicating A2 segment. Anatomically, after it sends off from the callosomarginal artery (CMA), it continues as the pericallosal artery (PCalA). A detailed pattern of the anatomical variations of the PCalA are needed for practical reasons. (2) Methods: There were 45 retrospectively documented Computed Tomography Angiograms of 32 males and 13 females. (3) Results: In 90 sides, eleven different types of PCalA were documented: type 1: normal origin, above the genu of the corpus callosum (CC) (51.11%); type 2: low origin, below the rostrum of the CC (8.88%); type 3: late origin, above the body of the CC (3.33%); type 4, initial transcallosal course (3.33%); type 5, duplicated PCalA (1.11%); type 6, azygos PCalA (2.22%); type 7, absent PCalA (CMA type of ACA) (7.78%); type 8: CMA continued as PCalA (5.56%); type 9: PCalA continued as the cingular branch (1.11%); type 10: PCalA type of ACA, absent CMA (14.44%); type 11: triple PCalA, with an added median artery of the CC (1.11%). Different types of CMA were also documented: type 0, absent CMA (17.78%); type 1, CMA with frontoparietal distribution (45.56%); type 2, CMA with parietal distribution (22.22%); type 3, low origin of CMA, either from A1, or from A2 (8.88%); type 4, CMA continued as PCalA (5.56%). Ipsilateral combinations of PCalA and CMA types were classified as types A-P. In 33/45 cases (73.3%), the bilateral asymmetry of the combined anatomical patterns of PCalA and CMA was documented. Additional rare variations were found: (a) huge fenestration of A2; (b) bihemispheric ACAs (6/45 cases); (c) twisted arteries within the interhemispheric fissure. (4) Conclusions: The PCalA and CMA are anatomically diverse and unpredictable. Therefore, they should be documented on a case-by-case basis before surgical or endovascular approaches.

The Infraoptic or Infrachiasmatic Course of the Anterior Cerebral Artery Emerging an Elongated Internal Carotid Artery.

(1) Background: The normal A1 segment of the anterior cerebral artery (ACA) has a supraoptic course. The proximal infraoptic course of an A1 segment leaving the internal carotid artery (ICA) near the origin of the ophthalmic artery is a rare possibility. This study aimed to determine the prevalence and detailed anatomy of infraoptic A1 segments. (2) Methods: We retrospectively studied 145 computed tomography angiograms from 92 male and 53 female cases, with ages varying from 61 to 78 y.o. (3) Results: In 21/145 cases, infraoptic or infrachiasmatic horizontal-medial courses of A1 segments that emerged distally from the ICA were found. Distal infraoptic A1 segments were bilateral in 16/145 cases and unilateral in 3/145 cases. Infrachiasmatic A1 segments were found bilaterally in 2/145 male cases. All the infraoptic/infrachiasmatic A1 segments left long ICAs with low bifurcations. In 7/34 sides with distal infraoptic or infrachiasmatic A1 segments, supracarotid courses were present. In one female, the right A1 segment had an anterior supraclinoid, supracarotid and infraoptic course. In two female cases with a bilateral distal infraoptic A1, the segment was almost contacting the respective posterior cerebral artery. (4) Conclusions: In cases with dolicho(ectatic) ICAs, the A1 segments could have infraoptic and supracarotid courses the neurosurgeons should be aware of.

Circle of Willis variation and outcome after intra-arterial treatment

BackgroundIntra-arterial treatment (IAT) improves outcomes in acute ischaemic stroke. Presence of collaterals increases likelihood of good outcome. We investigated whether variations in the circle of Willis (CoW) and contributing carotid...

A1-A2 anterior cerebral artery fenestration. a case report of a rare anatomical variant

Cerebral vascular anatomical variations are not uncommon in the human population. Their prevalence is not exactly known, as most of them are incidentally diagnosed on angiography or postmortem dissections. We present a rare fenestration of the A1 segment of the anterior cerebral artery presenting with a ruptured saccular aneurysm. A 42-year-old hypertensive patient presented unconscious following a ruptured saccular aneurysm. The computer tomography angiography showed a fenestration of the right A1 segment of the anterior cerebral artery (ACA). The medial segment of the A1 was communicating with the left ACA via the Anterior communicating artery, while the lateral segment was directly joining the A2 segment of the same side. Intraoperatively, the two segments were identified as separate vascular structures not sharing adventitia, and of equal caliber. The aneurysm arising from the bifurcation was clipped. The patient recovered with no neurological deficits. Many vascular anomalies like fenestrations and bifurcations are underdiagnosed, as many of them remain asymptomatic and are discovered incidentally on postmortem dissection or angiography for other pathologies. This has led to a paucity of cases to determine the prevalence in the human population. Good knowledge of the vascular anatomy variations and associated risk of aneurysm is important for the vascular neurosurgeons.

Microneurosurgical management of aneurysms of the A1 segment of the anterior cerebral artery: Anatomy and surgical technique.

Background: Aneurysms of the A1 segment of the anterior cerebral artery (ACA) are rare and have characteristics differentiating them from other intracranial aneurysms. Their microsurgical management is challenging and requires different strategies. In this article, we review the surgical anatomy of the A1 segment of the ACA with cadaveric dissections and describe the microsurgical management of complex A1 aneurysms with illustrative cases.Methods: A right pterional craniotomy and Sylvian dissection were performed on a formalin-fixed and silicone-injected cadaver head to depict the key anatomic structures and surgical corridors for microsurgical clipping of A1 segment aneurysms. The microneurosurgical management of ruptured and unruptured aneurysms of the A1 segment of the ACA is described with case illustrations.Results: The A1 segment of the ACA can be subdivided into proximal, middle, and distal subsegments, the former having abundant perforating branches. Both patients treated with microsurgical clipping had excellent and durable outcomes and postoperative cerebral angiograms showed complete aneurysm occlusion.Conclusion: Small A1 aneurysms may require early treatment as their rupture risk appears to be higher. A1 aneurysms are usually embedded in perforators, especially those arising from the proximal A1 subsegment, and require careful distal to proximal microdissection and strategic placement of the aneurysm clip blades. The approach, arachnoid dissection, and angles of attack are carefully planned after accounting for the aneurysm dome projection, precise location of the aneurysm neck and perforators, and the presence or absence of subarachnoid hemorrhage.

Association of dissection features and primary collateral circulation with ischemic stroke in patients with spontaneous internal carotid artery dissection: evaluated using vessel wall-MRI and MRA.

To study the ischemic stroke risk factors in spontaneous internal carotid artery dissection (ICAD) patients via analyzing the dissection features and primary collateral circulation using vessel wall-MRI and magnetic resonance angiography. ICAD patients who had undergone VW-MRI were included in this study. A total of 36 patients were included and divided into ICAD stroke (N = 23) and non-stroke (N = 13) group. Dissection imaging features [intramural hematoma (IMH), length of IMH, intimal flap, double lumen, intraluminal thrombus, degree of stenosis] and primary collateral status were analyzed. The primary collateral score (0-4) was evaluated based on presence of anterior communicating and ipsilateral anterior cerebral artery A1 segment (0-2) and ipsilateral posterior communicating artery (0-2). There were no significant differences in dissection imaging features such as presence of double lumen, intimal flap, IMH, length of IMH and intraluminal thrombus between the two groups. Degree of stenosis and primary collateral score showed significant differences between the two groups. Both the poor primary collateral circulation and severe stenosis may play an important role in occurrence of ischemic stroke for spontaneous ICAD patients and good primary collateral circulation can help to reduce the incidence of infarction. ICAD is one of the major causes of ischemic stroke. Early evaluation of the status of the Circle of Willis in ICAD patients by MRI may help to make treatment strategies and improve clinical outcome.

Stenosis of Azygos Anterior Cerebral Artery Results in Bilateral Anterior Cerebral Artery Strokes.

HomeStrokeVol. 53, No. 10Stenosis of Azygos Anterior Cerebral Artery Results in Bilateral Anterior Cerebral Artery Strokes Free AccessCase ReportPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessCase ReportPDF/EPUBStenosis of Azygos Anterior Cerebral Artery Results in Bilateral Anterior Cerebral Artery Strokes Diana Yang, Brian Behdad Miremadi, Anton Mlikotic and Kassi Kronfeld Diana YangDiana Yang Correspondence to: Diana Yang, DO, Harbor-UCLA Medical Center, 1000 W. Carson St, Building N-25, Torrance, CA 90502. Email E-mail Address: [email protected] https://orcid.org/0000-0001-6695-1771 Department of Neurology (D.Y., B.B.M., K.K.), Harbor-UCLA Medical Center, Torrance, CA. Search for more papers by this author , Brian Behdad MiremadiBrian Behdad Miremadi Department of Neurology (D.Y., B.B.M., K.K.), Harbor-UCLA Medical Center, Torrance, CA. Search for more papers by this author , Anton MlikoticAnton Mlikotic Department of Radiology (A.M.), Harbor-UCLA Medical Center, Torrance, CA. Search for more papers by this author and Kassi KronfeldKassi Kronfeld Department of Neurology (D.Y., B.B.M., K.K.), Harbor-UCLA Medical Center, Torrance, CA. Search for more papers by this author Originally published15 Jul 2022https://doi.org/10.1161/STROKEAHA.122.040216Stroke. 2022;53:e448–e449Other version(s) of this articleYou are viewing the most recent version of this article. Previous versions: July 15, 2022: Ahead of Print KEY POINTAlthough much rarer than unilateral extremity weakness, bilateral lower extremity weakness may still result from a stroke—specifically due to vascular compromise of an azygos anterior cerebral artery.A 55-year-old female presented with 1 week of acute onset bilateral lower extremity weakness and reduced speech output. Examination was notable for spastic paralysis of lower extremities, trace weakness in bilateral shoulder abduction, and abulia. Magnetic resonance imaging revealed bilateral anterior cerebral artery (ACA) territory strokes. Computed tomography angiography demonstrated absence of the anterior communicating artery, a hypoplastic right ACA precommunicating segment (A1), azygos continuation of a dominant left ACA, and focal stenosis in the lone A2 segment.ACA territory infarcts only account for 1.8% of cerebral infarcts, and bilateral ACA infarcts are even less common.1 Azygos ACA is a rare circle of Willis variant (0.3%–2% of the population) notable for an absent anterior communicating artery and one ACA postcommunicating segment (A2) feeding both ACA territories.2 Despite the initial difficult localization, bilateral lower extremity weakness may still result from a stroke, specifically due to vascular compromise of an azygos ACA (Figure).Download figureDownload PowerPointFigure. Brain magnetic resonance imaging and head computed tomography angiography. Bilateral anterior cerebral artery (ACA) territory diffusion restriction on magnetic resonance imaging diffusion-weighted imaging (DWI) sequence (A) with corresponding hyperintensity on fluid-attenuated inversion recovery (FLAIR) sequence (B). Three-dimensional computed tomography angiography (C and D) demonstrates 2 anatomic variants: hypoplastic right A1 segment (short arrow) with dominant left ACA and an absent anterior communicating artery. There is significant focal stenosis in the A2 segment (long arrows).Article InformationSources of FundingNone.Disclosures None.FootnotesFor Sources of Funding and Disclosures, see page e449.Correspondence to: Diana Yang, DO, Harbor-UCLA Medical Center, 1000 W. Carson St, Building N-25, Torrance, CA 90502. Email [email protected]lacounty.gov

A novel self-expanding shape memory polymer coil for intracranial aneurysm embolization: 1 year follow-up in Chile

BackgroundAneurysm recurrence remains a challenge when coiling cerebral aneurysms. Development of next generation coils has focused on accelerating thrombus maturation and increasing coil packing density. Ultra low density shape memory...

Coaptation Reserve Predicts Optimal Reduction in Mitral Regurgitation and Long-Term Survival With Transcatheter Edge-to-Edge Repair.

Although transcatheter edge-to-edge repair (TEER) is effective and safe, there is a need for better prediction of optimal outcomes. We aimed to determine predictors of optimal reduction in mitral regurgitation (MR) and survival with TEER. We examined mitral anatomy and its change with TEER on outcomes in 183 patients (age, 82 [77-87] years; 53% women). Coaptation reserve was measured as the distance of continuous apposition of the A2 and P2 leaflet segments in 2-dimensional apical long-axis imaging at the site of the predominant jet of MR. Augmentation in coaptation was measured as the total amount of leaflet insertion. Addressable coaptation area was calculated using the physical boundaries of the TEER device. Coaptation reserve, its augmentation, and addressable coaptation area were strong predictors of MR reduction (all P<0.001), as well as heart failure hospitalization and death. For patients with either mild or no residual MR, median values for coaptation reserve, its augmentation, and addressable coaptation area were 3.7 (2.8-4.5) mm, 7.3 (5.2-9.5) mm, and 59.0 (48.0-71.8) mm2, respectively. Receiver operating characteristic analyses determined the best values for optimal MR reduction as a coaptation reserve of >3.0 mm (P<0.001), addressable coaptation area of ≥52 mm2 (P<0.001), and coaptation augmentation of ≥4.7 mm (P<0.001). These values were associated with greater 2-year survival free of all-cause mortality and persisting even in analyses restricted to those with mild or no residual MR after TEER. Coaptation reserve and its augmentation are simple, independent parameters that predict optimal MR reduction and better survival in patients undergoing TEER. These findings may have implications for patient selection and expanded use of the therapy.